Acute/grave accents: upper case versus low case

You find the isolated acute accent used for capital letters in the encoding TS1, where it's called \capitalacute:

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage{textcomp}
\begin{document}
\capitalacute{A}\'{A}\\
\capitalacute{}\'{}\\
{\fontencoding{TS1}\selectfont\char 1}\char1
\end{document}

You maybe able to do minor adjustments using the slant dimension.

Here is some code I had for a similar issue:

\documentclass[10pt]{article}

\usepackage{graphicx} 


\begin{document}

\font \romanfont=cmr10
\font\specroman=cmr10
%% Next, the special registers
\newdimen\savedvalue
\savedvalue=\fontdimen5\romanfont
\newdimen\specialvalue
\specialvalue=4.75pt
%% Finally, definitions.

\def\specrm{%
  \aftergroup\restoredimen
  \fontdimen5\specroman=\specialvalue
  \specroman  }
\def\restoredimen{%
\fontdimen5\romanfont=\savedvalue }


 \scalebox{10}{\romanfont \'A}  {\scalebox{10}{\specrm \' A}}

\medskip
{\noindent\obeylines\specrm 
the value of fontdimen1 (slant)  is \the\fontdimen1\font
the value of fontdimen2 (interword space) is \the\fontdimen2\font  
the value of fontdimen3 (interword stretch) is \the\fontdimen3\font 
the value of fontdimen4 (interword shrink) is \the\fontdimen4\font 
the value of fontdimen5 (x-height) is \the\fontdimen5\font 
the value of fontdimen6 (quad width) is \the\fontdimen6\font 
the value of fontdimen7 (extra space)  is \the\fontdimen7\font 
}
\medskip

\font \romanfont=cmr10
\font\specroman=cmr10
%% Next, the special registers
\newdimen\savedvalue
\savedvalue=\fontdimen1\romanfont
\newdimen\specialvalue
\specialvalue=0.15pt
%% Finally, definitions.

\def\specrm{%
  \aftergroup\restoredimen
  \fontdimen1\specroman=\specialvalue
  \specroman  }
\def\restoredimen{%
\fontdimen1\romanfont=\savedvalue }


 \scalebox{10}{\romanfont \'A}  {\scalebox{10}{\specrm \' A}}

\medskip
{\noindent\obeylines\specrm 
the value of fontdimen1 (slant)  is \the\fontdimen1\font
the value of fontdimen2 (interword space) is \the\fontdimen2\font  
the value of fontdimen3 (interword stretch) is \the\fontdimen3\font 
the value of fontdimen4 (interword shrink) is \the\fontdimen4\font 
the value of fontdimen5 (x-height) is \the\fontdimen5\font 
the value of fontdimen6 (quad width) is \the\fontdimen6\font 
the value of fontdimen7 (extra space)  is \the\fontdimen7\font 
}
\end{document}

There is also a package you can have a look at https://github.com/zellyn/accentbx